Heat exchanger inlet tank with inmolded inlet radius feature

ABSTRACT

A heat exchanger inlet tank including a housing having an inner surface and an outer surface and an inlet connector having an inner surface substantially continuous with the inner surface of the housing. The inner surface of the inlet connector and the inner surface of the housing converging to form an inlet interface. The heat exchanger further includes a protuberance disposed on the inner surface of the housing configured to militate against a pressure drop of a fluid flowing through the inlet tank.

FIELD OF THE INVENTION

The present invention relates to an inlet tank for use with a heat exchanger in a vehicle, and more particularly to an inlet tank radius feature for use with a heat exchanger in a vehicle.

BACKGROUND OF THE INVENTION

As commonly known, heat exchangers such as a radiator are configured to change a temperature of various working fluids such as an engine coolant, an engine lubricating oil, an air conditioning refrigerant, and an automatic transmission fluid, for example. The heat exchanger typically includes spaced apart fluid conduits or tubes connected between an inlet tank and an outlet tank, and a final disposed between adjacent conduits. The working fluid enters the inlet tank through an inlet port, then flows through the fluid conduits or tubes, and exits the outlet tank through an outlet port. Air is directed across the fins. As the air flows across the fins, heat from the working fluid flowing through the tubes is conducted through walls of the tubes, into the fins, and into the air. The inlet tank is therefore configured as a fluid manifold to distribute the working fluid from the inlet port to the tubes.

The inlet tank typically includes a housing and an inlet connector or pipe that defines the inlet port. The inlet connector is typically formed in a side of the housing and extends outwardly therefrom. The inlet connector may be configured for coupling to a pipeline or hose of a vehicle in order to feed the circulating working fluid into the inlet tank. A sharp edge is formed at an inlet interface on an inner surface of the housing and an inner surface of the inlet connector. Undesirably, the sharp edge disrupts a bulk velocity of the working fluid flowing through the inlet tank which results in an increase in a pressure drop of the working fluid as the working fluid enters the inlet tank. The increase in the pressure drop reduces a thermal efficiency of the radiator. Therefore, it is desirable to form a radiused inlet edge on the inlet connector at the inlet interface instead of a sharp edge to minimize the pressure drop of the working fluid as the working fluid enters the inlet tank.

However, inlet tanks for heat exchangers are typically formed by a molding process, wherein the inlet tank and the inlet connector are formed integrally. Due to a direction of draw of molding tools, forming the inlet connector requires a special molding device such as a core or cavity projection that will retract during the molding process. Forming a feature on the inlet connector to form a radiused inlet edge complicates a design of the molding tool and a design of the special molding device and increases the cost of the molding process.

Therefore, it would be desirable to produce an inlet tank of a heat exchanger having a feature to form a radiused inlet edge, wherein a thermal efficiency of the heat exchanger is maximized and complexity of manufacturing and costs are minimized. It would be advantageous if an inlet tank of a heat exchanger could be improved.

SUMMARY OF THE INVENTION

Concordant and congruous with the present invention, an improvement of an inlet tank of a heat exchanger has been discovered.

According to an embodiment a heat exchanger inlet tank is disclosed. The heat exchanger inlet tank includes a housing having an inner surface and an outer surface and an inlet connector having an inner surface substantially continuous with the inner surface of the housing. The inner surface of the inlet connector and the inner surface of the housing converge to form an inlet interface. The heat exchanger inlet tank further includes a protuberance disposed on the inner surface of the housing configured to militate against a pressure drop of a fluid flowing through the inlet tank.

According to another embodiment a heat exchanger inlet tank includes a housing having an inner surface and an outer surface and an inlet connector integrally formed with and extending outwardly from the outer surface of the housing. The inlet connector having an inner surface substantially continuous with the inner surface of the housing. The heat exchanger inlet tank further includes an inlet interface formed at a convergence of the inner surface of the housing and the inner surface of the inlet connector and a protuberance disposed on the inner surface of the housing extending from at least a portion of the inlet interface along the inner surface of the housing.

According to a further embodiment a heat exchanger is disclosed. The heat exchanger includes an inlet tank including a housing having an inner surface and an outer surface and an inlet connector having an inner surface substantially continuous with the inner surface of the housing. The inner surface of the inlet connector and the inner surface of the housing converging to form an inlet interface. The heat exchanger further includes a protuberance having a substantially arcuate cross-section disposed on the inner surface of the housing extending from at least a portion of the inlet interface along the inner surface of the housing to a transitional portion of the inner surface of the housing. A concave indentation corresponding to the protuberance is formed on the outer surface of the housing. A plurality of tubes extend from and are in fluid communication with the inlet tank.

BRIEF DESCRIPTION OF THE DRAWINGS

The above, as well as other advantages of the present invention, will become readily apparent to those skilled in the art from the following detailed description of a preferred embodiment when considered in the light of the accompanying drawings in which:

FIG. 1 is a fragmentary top perspective view of a heat exchanger according to an embodiment of the invention;

FIG. 2 is a fragmentary bottom plan view of an inlet tank of the heat exchanger illustrated in FIG. 1;

FIG. 3 is a fragmentary bottom perspective view of the inlet tank of FIGS. 1 and 2;

FIG. 4 is a broken rear elevational view of the inlet tank of the heat exchanger illustrated in FIG. 1;

FIG. 5 is a cross-sectional view taken along the line 5-5 of FIG. 4;

FIG. 6 is a fragmentary cross-sectional view taken along the line 6-6 of FIG. 4;

FIG. 7 is a cross-sectional view taken along the line 5-5 of FIG. 4 according to another embodiment of the invention; and

FIG. 8 is a fragmentary cross-sectional view taken along the line 6-6 of FIG. 4 according to another embodiment of the invention.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS OF THE INVENTION

The following detailed description and appended drawings describe and illustrate various exemplary embodiments of the invention. The description and drawings serve to enable one skilled in the art to make and use the invention, and are not intended to limit the scope of the invention in any manner.

FIG. 1 illustrates a heat exchanger 10 according to an embodiment of the invention. The heat exchanger 10 can be used, for example, as a radiator for cooling a liquid coolant for an engine of a vehicle. The heat exchanger 10 includes a heat exchange core 12 and a housing 20. The heat exchange core 12 includes a plurality of substantially parallel tubes 14 and a plurality of substantially parallel fins 16 interposed between the tubes 12. In the embodiment shown, the heat exchanger 10 is a parallel flow type heat exchanger commonly referred to as a radiator. However, it should be understood that other types of heat exchangers can be used such as a serpentine-flow type heat exchanger and a U-flow type heat exchanger. Additionally, while the embodiment shown includes the heat exchange core 12 with the tubes 14 and the fins 16, it is understood the invention can be used in conjunction with various types of heat exchange cores.

The tubes 14 are configured to contain and convey a fluid to facilitate heat transfer. The fluid can be any fluid configured to facilitate heat transfer such as engine coolant, an engine lubricating oil, an air conditioning refrigerant, and an automatic transmission fluid, for example. The tubes 14 extend laterally from and are in fluid communication with the housing 20. Further, the tubes 14 extend substantially perpendicular relative to the housing 20. The tubes 14 can extend between the housing 20 and an outlet tank (not shown) adapted to provide an exit for the fluid flowing through the heat exchanger 10. The fins 16 are in thermal communication with the tubes 14 and are adapted to allow a flow of air to pass therebetween, and further allow the flow of air to pass between the tubes 14 to facilitate transfer of heat from the air to the fins 16 to the tubes 14 and to the fluid or from the fluid to the tubes 14 to the fins 16 and to the air. The fins 16 may have a corrugated shape.

As shown in FIGS. 1-3, the housing 20 is elongate and adapted to convey a flow of the fluid from a source of fluid (not shown) to the tubes 14. The housing 20 includes a chamber 30 having a tube perimeter 22 defining an opening 28. The housing 20 further includes a substantially arcuate wall 24 extending between opposing end walls 26, a substantially smooth inner surface 34, and an outer surface 35. The arcuate wall 24 and the end walls 26 extend from the tube perimeter 22 to form the chamber 30 to receive the fluid. The chamber 30 can be enclosed by a plate not shown) disposed in the opening 28 with a plurality of tube openings (not shown) for receiving the tubes 14. The plate is bounded by the tube perimeter 22 and can be integrally formed with the housing 20 or the plate can be separately formed from the housing 20 and coupled thereto. In the embodiment shown, the housing 20 has a substantially semi-cylindrical shape. However, the housing 20 can have a rectangular shape having five walls or any other shape as desired such as around, ovular, ellipsoidal, and triangular, for example.

The housing 20 further includes an inlet connector 40 disposed at a first end 32 thereof and adapted to provide fluid communication between the source of fluid and the housing 20. As shown, the inlet connector 40 is integrally formed with the housing 20 and extends outwardly from the outer surface 35 of the housing 20. The inlet connector 40 defines an inlet port 42 to the chamber 30. The inlet connector 40 is substantially perpendicular in respect of a longitudinal direction of the housing 20. However, the inlet connector 40 can also be formed at an angle in respect of the housing 20. The inlet connector 40 has a generally cylindrical shape and has an inner diameter d. In the embodiment shown, the inlet connector 40 has a truncated cylindrical shape due to the semi-cylindrical shape of the housing 20. However, the inlet connector 40 can have any shape as desired. Additionally, the inlet connector 40 can extend from any position on the housing 20 such as a center, one of the opposing end walls 26, or a second end 33, for example.

A substantially smooth inner surface 44 of the inlet connector 40 is substantially continuous with the substantially smooth inner surface 34 of the housing 20. The inner surface 44 of the inlet connector 40 and the inner surface 34 of the housing 20 converge to form an inlet interface 50. The inlet interface 50 includes a first edge portion 52 and a second edge portion 54. The first edge portion 52 corresponds to a portion of the inlet interface 50 that extends along a first arc of curvature a₁ thereof. The second edge portion 54 corresponds to a portion of the inlet interface 50 that extends along a second arc of curvature a₂ thereof. The first edge portion 52 corresponds to a portion of the inlet interface 50 where an edge radius can be formed, where an edge radius is an arcuate or rounded edge. It is understood that the first edge portion 52 can also extend along the entire inlet interface 50.

The housing 20 further includes a protuberance 60 integrally formed with and extending outwardly from the inner surface 34 of the housing 20. The protuberance 60 is generally convex with respect to the inner surface 34 of the housing 20. The protuberance 60 is substantially continuous with the inlet interface 50 and extends longitudinally along the inner surface 34 of the housing 20 from the first edge portion 52 of the inlet interface 50 towards the second end 33 of the housing 20 to a transitional portion 38 of the inner surface 32 of the housing 20. The transitional portion 38 and the first edge portion 52 of the inlet interface 30 form a perimeter of the protuberance 60. A width w_(p) of the protuberance 60 can vary along a length l_(p) thereof and the length l_(p) of the protuberance 60 can vary along a width w_(p) thereof. In the embodiment shown, the protuberance 60 has a generally parabolic or slightly crescent shaped perimeter. However, the protuberance 60 can have a perimeter having any shape as desired such as fan shaped, rectangular, kidney shaped, ovular, or any other shape to minimize a pressure drop of the fluid flowing through the housing 20.

In the embodiment shown in FIG. 5, the protuberance 60 has a cross-section that is generally arcuate or camber-shaped to facilitate a smooth flow of the fluid through the housing 20. However, it is understood, the protuberance 60 can have other cross-sectional shapes as desired such as a serpentine shaped, saddle shaped, semi-circular shaped, wedge shaped, or any other shape as desired to minimize a pressure drop of the fluid flowing through the housing 20. A height h_(p) of the protuberance 60 with respect of the inner surface 34 of the housing 20 varies along the width thereof w_(p). For example, as shown in FIG. 5, the protuberance 60 has a first tapered side 66 tapering towards the tube perimeter 22 to the transitional portion 38. The protuberance 60 also has a second tapered side 68 tapering towards a base 36 of the arcuate wall 24 to the transitional portion 38 of the inner surface 34 of the housing 20 such that a substantially smooth surface is formed at the transition portion 38. A width w_(T1) of the first tapered side 66 can be substantially equal to a width w_(T2) of the second tapered side 68. However, the width w_(T1) of the first tapered side 66 can be smaller or larger than the width w_(T2) of second tapered end 68 to facilitate minimizing a pressure drop of the fluid flowing through the housing 20, as desired. In a non-limiting example as shown in FIG. 5, the width w_(T1) of the first tapered side 66 can be less than the width w_(T2) of the second tapered side 68. Additionally, the first tapered side 66 can have a taper that is steeper than the second tapered side 68 or the second tapered side 68 can have a steeper taper than the first tapered side 66. Furthermore, as shown in FIG. 5, the protuberance 60 slightly curves along the width w_(p) thereof with the inner surface 34 of the housing 20 to provide an substantially smooth transition at the transitional portion 38 and to conform to the semi-cylindrical cross-sectional shape of the housing 20. However, it is understood that the protruberance 60 can be adapted to conform to any shape of the housing 20 as desired such as a rectangular shape having five walls or any other shape as desired, such as obround, ovular, ellipsoidal, and triangular, for example.

In the embodiment shown in FIG. 6, the protuberance 60 has a cross-section that is arcuate or camber-shaped to facilitate a smooth flow of fluid through the housing 20. However, it is understood, the protuberance can have other cross-sectional shapes as desired such as a serpentine shaped, saddle shaped, semi-circular, wedge shaped, or any other shape as desired to minimize a pressure drop of the fluid across the protuberance 60 and through the housing 20. The height h_(p) of the protuberance 60 with respect of the inner surface 34 of the housing 20 varies along a length l_(p) thereof As shown in FIG. 6, the protuberance 60 has a first tapered end 62 tapering towards the inlet interface 50 forming the radiused edge at the inlet interface 50. The protuberance 60 can also have a second tapered end 64 tapering towards the second end 33 of the housing 20 to the transitional portion 38 of the inner surface 34 of the housing 20 such that a substantially smooth surface is formed at the transition portion 38. A length l_(T1) of the first tapered end 62 is substantially equal to a length l_(T2) of the second tapered end 64. However, the length l_(T2) of the first tapered end 62 can be smaller or larger than the length l_(T2) of second tapered end 64 to facilitate minimizing a pressure drop of the fluid across the protuberance 60 and through the housing 20, as desired. In a non-limiting example, the length l_(T1) of the first tapered end 62 can be less than the length l_(T2) of the second tapered end 64 such that the first tapered end 62 has as steeper taper than the taper of the second tapered end 64. Additionally, the first tapered end 62 can have a taper that is steeper than the taper of the second tapered end 64 and the second tapered end 64 can have a taper that is steeper than the taper of the first tapered end 62.

In the embodiment shown in FIG. 5 and FIG. 6, the housing 20 has a wall thickness t_(c). The protuberance 60 has a wall thickness t_(p) larger than the wall thickness t_(1p) of the housing 20. The wall thickness l_(p) of the protuberance can vary as the height h_(p) varies along the length l_(p) and the width w_(p) thereof. However, FIG. 7 and FIG. 8 illustrate another embodiment. Structure similar to FIG. 5 and FIG. 6 includes the same reference numeral and a prime 0 symbol for clarity. The wall thickness t_(p′) of the protuberance 60′ can be substantially uniform with and substantially equal to the wall thickness of the housing 20′ to facilitate an improved molding process. According to this embodiment, a concave indentation 170 is formed on the outer surface 35′ of the housing 20′. The concave indentation 170 corresponds to the protuberance 60′ and is adapted to conform with the shape of the protuberance 60′ on the inner surface 34′ of the housing 20′ to maintain a uniform thickness between the thickness t_(c′) of the housing 20′ and the thickness t_(p′) of the protuberance 60′.

The protuberance 60 can have any shape, length l_(p), width w_(p), thickness t_(p) or height h_(p) as desired to minimize the pressure drop of the fluid flowing through the housing 20. In a non-limiting example, the length l_(p) and the width w_(p) of the protuberance 60 can be 1 to 2 times the inner diameter d of the inlet connector 40. In another non-limiting example, the height h_(p) of the protuberance 60 in respect of the inner surface 34 of the housing 20 can be 0.08-0.2 times the inner diameter d of the inlet connector 40. Additionally, while the protuberance 60 shown in FIG. 3, only circumscribes a portion of the inlet port 42 at the first edge portion 52, it is understood the protuberance 60 can circumscribe any portion of inlet port 42 such as circumscribing the entire inlet port 42.

The housing 20 can be composed of plastic and formed from a molding process such as injection molding, for example. The protuberance 60 can be formed by a feature on a mold in an injection molding process such that the protuberance 60 is integrally molded with the housing 20. The housing 20 and the protuberance 60 can be adapted to allow for adequate molding die draw. For example, the protuberance 60 is tapered to facilitate removal from the mold. It should be understood that the housing 20 and the protuberance 60 can be formed by other processes such as metal stamping, for example. Although the housing 20 and the protuberance 60 can be formed employing other suitable methods now known or later developed. Additionally, the protuberance 60 can be separately formed and coupled with the housing 20, as desired.

In use, the fluid is caused to flow from the source of fluid through the housing 20 to be distributed to the tubes 14. The fluid can be any conventional fluid such as a coolant fluid, an automatic transmission fluid, a power steering fluid, or an engine oil, for example. The fluid enters the housing 20 by flowing through the inlet connector 40 and then flowing into the chamber 30 at a bulk velocity. As the fluid flows from the inlet connector 40 to the chamber 30, the fluid flows over the protuberance 60 which forms the radiused edge at the inlet interface 50. The protuberance 60 is adapted to minimize a decrease in bulk velocity of the fluid as the fluid transitions from the inlet connector 40 to the chamber 30. Minimizing a decrease in the bulk velocity of the fluid militates against a pressure drop of the fluid as the fluid transitions from the inlet connector 40 to the chamber 30, which in turn increases thermal efficiency of the heat exchanger 10. For example, the protuberance 60 on the housing 20 can be adapted to minimize the pressure drop from the inlet connector 40 to the chamber 30 by about 10% to 15% of a pressure drop of the housing 20 without the protuberance 60. However, lower or higher percentages can be realized depending on the type of housing 20 and the height h_(p), length l_(p), width w_(p), and thickness l_(p) of the protuberance 60.

Further, the protuberance 60 disposed on the housing 20 facilitates an ease of manufacturing and decreases a cost of manufacturing. For injection molding, because the protuberance 60 is disposed on the housing 20, a special retraction tool is not required for the forming of the connection inlet 40 in the molding process to militate against an inadequate molding die draw. While, embodiments shown in the illustrated figures, show a protuberance 60 disposed within the housing 20 to form a radiused edge at the inlet interface 50, it is understood the protuberance 60 can be included with a housing 20 having a feature formed on or included with the inlet connector 40 to also facilitate forming a radiused edge to militate against a pressure drop in the housing 20.

From the foregoing description, one ordinarily skilled in the art can easily ascertain the essential characteristics of this invention and, without departing from the spirit and scope thereof, can make various changes and modifications to the invention to adapt it to various usages and conditions. 

What is claimed is:
 1. A heat exchanger inlet tank, comprising: a housing having an inner surface and an outer surface; an inlet connector having an inner surface substantially continuous with the inner surface of the housing, the inner surface of the inlet connector and the inner surface of the housing converging to form an inlet interface; and a protuberance disposed on the inner surface of the housing configured to militate against a pressure drop of a fluid flowing through the inlet tank.
 2. The heat exchanger inlet tank of claim 1, wherein the protuberance extends from at least a portion of the inlet interface to a transitional portion of the inner surface of the housing.
 3. The heat exchanger inlet tank of claim 2, wherein the protuberance has a first tapered side, a second tapered side, a first tapered end, and a second tapered end, the first tapered side, the second tapered side, and the second tapered end tapering to the transitional portion, and the first tapered end tapering to the inlet interface.
 4. The heat exchanger inlet tank of claim 1, wherein the protuberance forms a radiused edge at the inlet interface.
 5. The heat exchanger inlet tank of claim 1, wherein the protuberance has a width varying along a length thereof.
 6. The heat exchanger inlet tank of claim 1, wherein the protuberance has a length that varies along a width thereof.
 7. The heat exchanger inlet tank of claim 1, wherein the protuberance has an arcuate cross-section.
 8. The heat exchanger inlet tank of claim 1, wherein a height of the protuberance in respect of the inner surface of the housing varies along a length of the protuberance.
 9. The heat exchanger inlet tank of claim 1, wherein a height of the protuberance in respect of the inner surface of the housing varies along a width of the protuberance.
 10. The heat exchanger inlet tank of claim 1, wherein a wall thickness of the protuberance is substantially equal to a wall thickness of the housing.
 11. The heat exchanger inlet tank of claim 1, wherein a concave indentation corresponding to the protuberance is formed on the outer surface of the housing.
 12. The heat exchanger inlet tank of claim 1, wherein the protuberance is integrally formed by one of injection molding and metal stamping.
 13. The heat exchanger inlet tank of claim 1, wherein the housing has a substantially semi-circular shape
 14. A heat exchanger inlet tank, comprising: a housing having an inner surface and an outer surface; an inlet connector integrally formed with and extending outwardly from the outer surface of the housing, the inlet connector having an inner surface substantially continuous with the inner surface of the housing; an inlet interface formed at a convergence of the inner surface of the housing and the inner surface of the inlet connector; and a protuberance disposed on the inner surface of the housing extending from at least a portion of the inlet interface along the inner surface of the housing.
 15. The heat exchanger inlet tank of claim 13, wherein the protuberance has at least one of a width varying along a length thereof and a length that varies along a width thereof.
 16. The heat exchanger inlet tank of claim 13, wherein the protuberance extends from the at least a portion of the inlet interface to a transitional portion of the inner surface of the housing.
 17. The heat exchanger inlet tank of claim 13, wherein a height of the protuberance in respect of the inner surface of the housing varies along a length of the protuberance.
 18. The heat exchanger inlet tank of claim 13, wherein a height of the protuberance in respect of the inner surface of the housing varies along a width of the protuberance.
 19. The heat exchanger inlet tank of claim 13, wherein a concave indentation corresponding to the protuberance is formed on the outer surface of the housing to maintain a substantially uniform wall thickness of the inlet teak.
 20. A heat exchanger, comprising: an inlet tank including a housing having an inner surface and an outer surface and an inlet connector having an inner surface substantially continuous with the inner surface of the housing, the inner surface of the inlet connector and the inner surface of the housing converging to form an inlet interface; a protuberance having a substantially arcuate cross-section disposed on the inner surface of the housing extending from at least a portion of the inlet interface along the inner surface of the housing to a transitional portion of the inner surface of the housing; a concave indentation corresponding to the protuberance formed on the outer surface of the housing; and a plurality of tubes extending from and in fluid communication with the inlet tank. 